1. Field of the Invention
The present invention relates to a colored composition for use in electrowetting displays, an image display structure and an electrowetting display device.
2. Description of the Related Art
In recent years, many organic dyes have been used in display materials, optical recording media, inkjet recording material, etc. In a case in which a dye is used in a coating process or an inkjet recording process, the dye is required to have a high molar absorption coefficient as well as high solubility in solvents in order to increase coloring efficiency.
Since a display utilizing an electrowetting method (EWD) has been reported in Nature (London), 425, 383 (2003), electrowetting displays have attracted attention as a new image display technology. Electrowetting displays employ an image forming method in which plural pixels filled with two phases formed by a hydrophilic medium and an oil-based color ink are arranged on a substrate, affinity for the hydrophilic medium interface or the oil-based color ink interface is controlled by on-off control of voltage application for each pixel, and image is displayed by spreading the oil-based color ink over the substrate/shrinking the oil-based color ink. Dyes for use in such electrowetting displays are required to have high solubility in hydrocarbon solvents.
Examples of known dyes for use in color filters (display materials) include various dipyrromethene metal complex compounds such as the following compounds (for example, see Japanese Patent Application Laid-Open (JP-A) No. 20089-292970)
